Improvement in sewing-machines



3 Sheets-Sheet 1.

- W. o. GROVBR. SEWING llAvClElINE.

No. 36,405. A Patented Sept. 9.' 1862.

3 Sheets-'Sheet 2.

W. 0. GROVER. SEWING MACHINE. Y

No. 36,4057 Paten-ted Sept.v9, 1862.

s'jg

3 Sheets-Sheet 3.

W. 0. GROVER. SEWING MACHINE.

No. 36.405. Patnted Sept. 9, 1862.

UNITnI STATES WM. O. GROVER, OF WEST ROXBURY, MASSACHUSETTS.

I'Mlaovewi I-:NT IN SEWING-MACHINES.

Specification forming part ofV Letters Patent No. 36,405,'dated September 9, 1862.1'

,To all whom 'it may concern:

Be it knownthat I, WILLIAM 0. GROVER,

lof West Roxbury, in the county of Norfolk andv State of. Massachusetts,have invented certain new and useful Improvements in Sewing- Machines; and'Ido hereby declare that the following, taken in connection wilh thedrawings, is a full, clear, and exact description thereof.

In the drawings, Figure 1 is a side elevation of the machine with certain portions of the platform or bed-plate removed to show-the working parts. Fig. 2 is a similar side elevation with the working parts in a different position. Fig. 3 is a front elevation with vparts of the platforml removed. AFigs.. Vand 5 are side-elevations, in detaihof the needle, the

thread-carrier, and the assistant looper. Figs.

6 and 9 arefelevations of the needle' and assistant looper. .F.igs. 7 and 8 are plans of the assistant looper and thread-carrier. Fig. 10 is a detail view, partlyin section and partly in elevation, of the 'mainrsh-a, thread-carrier stock, and apparatus for moving the same;`

and Fig. 11 is an elevation of the thread carrier stock, thecrank-piu-and sleeve being.

shownjin'section.4

My first improvements,y are applicable only to machines making what iscommonly termed the Grover it Baker or double-thread looped stitch; and' i t..consists in certain mechanism, for actuatingA the thread-carrier, and in coni- 'bining the sa-me with an assistant looper.

My second improvement was designed espevciallyfor use in such machines, but is applicable also .to other varieties of sewing-machines and it consists in certain apparatus for governing' the upperthread in its passage from fthebobbin to the needle.

In this speciica'tion I mean by the term thread-carrier7 an instrument, with an' eye near its end, thatv controls the lower thread, passing bights of it'through loops of the upper thread, and holding'loops ot' its ownthread in position lto be entered by the needle. This iny strument is often called the lower needle,77 as it isshaped somewhat-like an ordinary eyepointed needle. l

I shall call in this description that side ot' the-machinemarked Atheleft, and` thatlnarked B' the right, side of the machine; and I shall call the .end of the machine' nearest the needle the front, and the end nearest the rock-shaft the rear, of the machine. i

All parts of the machine are mounted on a platform or bed-plate, c, whose upper surface supports the material to be sewed. Attached to theupper part of4 thisbed-plate is an arin or bracket, b, in the front end ofwhichis supported an vordinary presser-foot, slide, and

spring, and from the' lower side ofthe bedplate descend two hangers, c c, in which, in proper boxes, is mounted the main shaft d.' At one end of this shaft's a crank-pin, d', taking into a slot in an arm, e, which mak'es'a part of or is secured to a rock-shaft, f, and from this rock-shaft projects the {needle-arm e. The

rock-shaft is pivoted, and rocks upon two pins in a manner well known in sewing-machines, r

and when the main-'shaft dis worked thev nee- (lle-arm will oscillate, causing theneedle g, attached thereto, to rise above and descend below material lying on the bed-plate O n the Inain shaftiskeyed a driving-pulley, h, and it 4also carries two cams, t' lr, which, aided by a spring, l, gire proper motions to'an ordinary four-motion Ieeding-surface, m. The

hub, out of which the cam 7c is cut, is, on the side nearest the right side of the machine,

pecially in Fig. l1, the sleeve passing-through the slot.. It is also drilled through just above the slot, and into this hole is slipped a loose sleeve, t", rounded or spheroidal on its periphery and boned out'c) lindrically. This sleeve isfree to slide on a stationary pin., 1", and the stock q can rock over the periphery ofthe sleeve, this pin and sleeveiforming a'pivot, on which the stock oscillates. When the main shaft revolves-the surface on n and the pin p and sleeve o revo-ive with it,- and as the sleevev If and pin 1^ tlorm` a pivot or center ofrvibration for the thread-carrier stock, the revolution 'of the sleeve o will cause the thread-carrier to vi,-. brateA from'froptgto rear of the nachie, 'and vice versa. As this stock is contined against a revolving plane out of perpendicular-to the piu r. In 'order to give these motions tothe.

stock with mathematical precision', the sleeve r should be on'its'periphery a-portion of a per feet sphere, and this sphere should be confined in the stock as a cap and ball-joint, and I in tend sometimes to use such a construction but that shown in thc-drawings is sufficientv for practical purposes, and cheaper.

Thev thread-carrier must vibrate from front to rear sufficiently far to seize, hold, and release loopsof upper or needle thread as usual,

and must vibrate-sidewise toa distance equal to its own width and the dia-meter of the need e.

Any clampor clampsmay be substituted-for tliepiece a so long as they permit the shaft -to revolve and thestock to move from front to rear and canse 'the stock to he held riuly 'against the inclined .surface,and an ordinary pin without a sleeve may revolve with the shaft and enter the slotin the stock, or the stock may lreceive its front and' rearward motion ,from some other instruinentality,while its sidewise motions are caused by the inclinedrevolviug plane surface. W'hen the shaft is revolved and thi ead supplied in any ordinary way to the needle vand thread-carrier, and cloth or other suitable material -is placed upon the table, thencedle will descend to its lowest. limit,as in Fig.2,

' will rise a little to open a loop, andthe threadcarrier, advanciugon the left side ofthe needle. will enter the loop. '-(See Figs. 4 and 7;) The needle then rises to its iull extent, and afterv leaving the cloth and before it enters it aga-in the cloth is fed and the thread-carrier has advanced to its full extent toward th e-rear of the machine and has retreated again, and while so doing has moved sidewise to the right, so as to be on the right side of the descending nee-- dle. As the needle continues to descend all parts arrive at the position shown in Figs. 5 and 8, and the needle enters between a loop of its own thread, a portion of lower thread,and the threadcarrier,' as clearly shown'in Figs.5 and 8. The needle continues then to descend I and the threadcarrier to retreat till the positions shown in Fig. 2 are again reached, and

before the parts reach the position shown in needle, luse in combination with it what I have termed an assistant looper, S; '.lhe act-ing partot' this instrument is a. small stationary surface lying in line, or4 nearly so,withlthe left side of the needle and to therear of it. This surfacerprojects below the lower'side ot the platform, and whe-n thethread-carrier is advanced to its utmost. flimit- (seegFig'i) lower thread'leads from the hole inthe table'through which the needlepassesv to theeye ofthe thread. carrier, andin so doing leads `alongthe. left side ofthe acting surface of theassistantlooper S. -W'hen the thread-carrier retreats thread is pulled through its'eye byau ordinary vibrating spring lying between the lower tension apparatus, t, and the carrier, andas'thetliread-v carrier mores over to the right the thread hangsv on the surface of' the assistant -looper by fricvtion and a part of the lower'thread is kept more completely out of the path of the upper needle than it would be lif it led directly from the cloth tothe eye of the carrier. This .action takes place for the reason that the assistantlooper forces the lower threadv first -to lead from the cloth rearward and downward to its surface, and then rearward,.sidewise, and downward 'to the eye of thethread-carrier. This'portion are short it acts very successfully, but even 1 then itis not absolutely necessary, although it r makes the machine more perfect and prevents missin-g of stitches. As before stated, this assistant louper and the mechanism for actuating the thread-carrier are useful only in machines making a Grover & Baker stitch. e

My other improveTnent is cheliy applicable Ato sewing-machines of that class, but isuseful in other varieties ot'se\viiig-niachines.; and this improvement has for its object the keeping of an equal tension on the thread,e`veu whenthe length of stitches is suddenly altered or a sudden jump is'made from thin to thick material,

or from one thickness to a number of thiclif` nesses of cloth or other goods, This contrivauce consists essentially of two tension apparatas or frictions applied to the ncedlc-thread, the one weaker than the other,and stationary, and the other stronger and reciprocating, the two acting in connection with an eye or leader on the needle-arm, and the latter moving in such manner that the stationaryfrictiou apparat-us prevents thread from failing. slackly in `the wayof the needlepoint as the latter penetrates the cloth, while at the same time slack thread is formed by the approach of the :nor ing toward the stationary tension.`

In the drawings the bobbiu holding thread for supply of the needle is shown at u. It is mounted loosely onaspiudlq and from it the thread is led through a reciprocating friction apparatus, @,in'ounted on a prolongation, 1r, of' the needle-arm r', which extends rearward from `the rockshat't. The thread is nextled through a stationary friction apparatus or thread'dragw, mounted on vany convenient stan-dard attach'edto the bed-plate, and thence" passes througha third friction contrivance or drag,y,near the end of the needle-arm'. These tension. ori'riction contrivances or threadf drags are, as reprsented in the drawings, composedof .disks mounted ou a spindle andpressed together by a spring. :These disks'areconcaved on their adjacentsides, except'at the edges, where they are' beveled away from eachother. or convex.` When thread is passed between them; it isnipped and--has a drag put on it, and a` turn may be taken around the spindle on which the disks-are supported. I

intend to adjust the pressure lof the springo'n the reciprocati-n'g'tension by a screw'nut,'(see Fig. 3,) and the springs on the other drags need i no adjustability, although they may have it.

, By looking at Figs. 2 and 3 it will be perceived that the drag .cis so mounted in relation to the drag y and the. needle-'arm Vpivot is in such relation to the two that the distance between m and yitincreases as the needle descends, and the distance between e and decreases during the'same time. The tension apparatus g'fis a very light one. Its sole purpose as atension apparatus is to lift up thread on one side ofthe needle as the latter ascends while still below the cloth, and thus prevent formation ot' a loop on that side of the needle opposite to that on 'which the thread-carrier enters. lts other oce is thatof an eye or leader for the tl1read,and any eye or p in serving as a leading-block may in some cases be substituted for it.

As before stated, the amount ot' friction imposed upouthe threadby r is lessconsidera,

ble thanthat imposed by e. The .sum of both is equal to that 'imposed byone tension when only one is used, asis ordinarily7 the case'.

I-nthe action of the machine, as the needle l. rises to the position Fig. lit takes thread oft' of the spool against the drag of -all. the tensions,

and as it descends it takes thread from m but as o approaches a: faster than lg/frecedes from zr, it follows that slack thread will form between 11 land a'. .(See Fig. 2.) Whenthe loop of upper-needle thread is released bythe thread-carrier backing out ot it the tension imposed by an will be sucient to draw that loop up to the cloth as the needle descends, and

if a long stitch is taken, ortheneedle passes suddenly lthroughathicker materiahthe extra thread required .will be 'taken from the slack ybetween w and o, and the drawing ont of this thread is retarded by the friction on a' only,

'instead of bythe whole dragon theft-bread. It'

therefore followszgthat thread willnever be stretched so as to spring back and prevent thc formation of' a loopvwh'en the needle ascends, and it'alsofollows that the y'threadlv'ri-ll be less liable to abrasiony in thel eye of the4 needle; and these ed'ects follow from the combination of a reciprocating and a stationary tension and au eye or leader acting as described. .'I have' describedth'e ystationary drag as im.v

posing less tension o n the thread than the' moving one, and it is best so to adjust them,

but the tension ofthe movable maybe as great or greater than that imposed by the station. ary and the same beneficial results follow, but the-action. will less perfect.

.A'ny proper or known instrumentalities for producing a drag or tension upon thread may be substituted for those described, 'provided they are mounted relatively to each other and uct substantially as described, and the spool :itself may be mounted where o is and have f'ance acting substantially as specitied,

2. Giving four motionsztoa thread-carrier by means ot' aninclined revolving surface, a pin or sleeve, and a pivot, the whole either acting on the stock or controlling-its motions, substantially asrspecitied.

3. In combination wit-ha thread-.carrierhaving four motions, a station-ary assistantlooper,

substantially such as described, the two acting in combination, substantially in the manner set forth.

4. In combination, a vibrating thre adtension, a stationary thread-tension, and an eye or leader on a needle-arm, when thethree are 'relatively arranged and act in combination,

substantially asA described, for the. purposes specified.

In testiinonywhereof'- I have hereunto'-sub scribed my name;

W. o. oneven.' In presence ofvJAMEs C. WADE, J Mes H. B aowN. 

